I set control panel to '5.1 surround speakers', and set the CCCP audio output to 'same as input'. I'm not sure at what level the problem is.

I have a DFI RS482 mATX motherboard, using the SPDIF output. The cable I found is really sketchy, with a loose plug, but it works on stereo right now, is it possible that it's not switching to DD because of some transmission errors?